Video images and other information are increasingly being stored on portable optical recording media such as DVDs and CDs for use at diversifying places. In response to this trend, optical disk devices are being installed in small equipment such as notebook personal computers. Accordingly, a smaller and lighter optical disk drive device for installing in small mobile equipment is also needed.
The recording capacity of optical disks continues to increase year by year. Reading speeds are also becoming faster. Optical disk devices thus need to be assembled with a high degree of accuracy, and require adjustment of their settings on a control board to ensure that each part of the assembled device can demonstrate its intended performance. In the optical disk device, the pickup and control board are generally coupled by a flexible cable, and thus this cable follows the sliding of the pickup. The slight changes in load applied to the pickup in response to this movement of the cable are adjusted and optimized in the above adjustment process. Accordingly, the flexible cable coupled to the pickup is protected with several chasses in the optical disk device during transportation and attachment to prevent any change in adjustment settings.
FIG. 6 is a perspective view of the appearance of a conventional optical disk device, FIG. 7 is a perspective view of the appearance of a mobile information processing apparatus in which the optical disk device shown in FIG. 6 is installed, and FIG. 8 is a plan view of the mobile information processing apparatus seen from the bottom and with a bottom case removed.
In FIG. 6, pickup 161 reads information on the recorded face of the optical disk (not illustrated). Pickup 161 includes a laser emitter, light-receiving element, and lens for focusing a laser beam onto the recording face of the optical disk. Pickup 161 is slideably attached to frame 165. The optical disk is set on spindle motor 164, and this motor rotates the optical disk. Spindle motor 164 is fixed to frame 165. Pickup module 110 is configured with pickup 161, spindle motor 164, and frame 165.
Frame 165 is fixed to tray case 162 by multiple elastic bodies (not illustrated). A reading signal output from pickup 161 is transmitted through the flexible cable (not illustrated) extending from pickup 161 to an amplifier circuit board disposed in tray case 162. Chassis (not illustrated) is fixed to the bottom face of tray case 162 so as to protect the cable from pickup 161.
The amplifier circuit board and control board 163 are coupled using another flexible cable 166. Control board 163 is fixed to drive case 169 and coupled to the circuit board (not illustrated) of a mobile information processing apparatus via interface connector 168 on control board 163. In general, the optical disk device is fixed to the mobile information processing apparatus using metal fitting 167 attached to drive case 169.
FIG. 7 is an example of the mobile information processing apparatus in which the conventional optical disk device is installed. FIG. 8 illustrates the same mobile information processing apparatus with the outer cover removed. The operation of the conventional optical disk device is described below for the case of installation in a mobile information processing apparatus.
In FIG. 7, the optical disk device such as a CD-ROM drive device or DVD-ROM drive device is installed on the left of main body 171 of the mobile information processing apparatus. As shown in the drawing, tray case 162 to which pickup module 110 is installed slides out on pressing disk eject button 172. This allows disk 173 to be placed. When tray case 162 is housed in main body 171, spindle motor 164 rotates disk 173.
In the mobile information processing apparatus, interface connector 168 fixed to drive case 169 electrically couples control board 163 of the optical disk device shown in FIG. 6 and circuit board 181 of the mobile information processing apparatus shown in FIG. 8. This enables transmission of information read from the optical disk device to circuit board 181 of the mobile information processing apparatus.
However, in the above conventional optical disk device, tray case 162, to which pickup module 110 is attached, is fitted to drive case 169 in an unstable contact state when tray case 162 is housed inside drive case 169. As a result, when the optical disk device is used in a condition affected by external vibrations, vibrations of tray case 162 inside drive case 169 are amplified, and thus the reading and writing characteristics of the optical disk device cannot be readily secured in some cases.
To prevent degradation of these characteristics, drive case 169 is generally retained with respect to a cabinet of the mobile information processing apparatus in which the optical disk device is installed via an elastic body. In this case, however, the elastic body disposed between drive case 169 and the cabinet and the elastic body disposed between frame 165 of pickup module 110 and tray case 162 may generate resonances. Accordingly, reading and writing characteristics of the optical disk device cannot be expected to improve.
The optical disk device disclosed in Japanese Patent Unexamined Application No. 2004-326499 is fixed to the casing of the mobile information processing apparatus directly or via a cushioning material. However, in the case of this type of conventional optical disk device, the characteristics cannot be adjusted depending on various factors, such as frictional resistance during sliding of the pickup, once the optical disk device is installed in the mobile information processing apparatus. Consequently, it has been difficult to secure performance of the optical disk device to a high degree of precision.